Two horizontal pipes are the same length,but pipe B has twice the diameter of pipe A.Water undergoes viscous flow in both pipes,subject to the same pressure difference across the lengths of the pipes.If the flow rate in pipe A is Q = $\frac { \Delta V } { \Delta t }$ ,what is the flow rate in pipe B?
A)2Q
B)4Q
C)8Q
D)16Q
E)Q $\sqrt { 2 }$

Question

Quizplus · Accepted Answer

The flow rate in a pipe is proportional to the fourth power of the diameter (Poiseuille's Law). Since pipe B has twice the diameter of pipe A, the flow rate in pipe B is $2^4 = 16$ times that of pipe A.

Two Horizontal Pipes Are the Same Length,but Pipe B Has ΔVΔt\frac { \Delta V } { \Delta t }ΔtΔV​

Two Horizontal Pipes Are the Same Length,but Pipe B Has $\frac { \Delta V } { \Delta t }$